NEW YORK -- In Javier Baez's first 12 games in the big leagues, he struck out 20 times, had 13 hits, including four home runs, and zero walks. That changed on Sunday when the hard-swinging Cubs rookie drew two walks against the Mets.

"I think that was a byproduct of the process of his at-bats," manager Rick Renteria said before Monday's 4-1 win in the series finale. "He was staying to his strengths, seeing the ball in his zone and not being too over anxious.

"Over the long haul, he understands that if he's swinging at pitches that are really unhandable, they're going to keep [throwing them], for sure," Renteria said. "He's 21 years old. He's learning."

Baez did what he does best in the ninth inning on Monday, belting a two-run homer into the second deck in left field. It was his fifth home run, and he is third Cubs player with five homers in his first 14 career games since Kevin Roberson (1993) and Carmelo Martinez (1983) did so.

"I just have to realize there's a guy behind me and they are going to pitch to me so they don't have to pitch to [Anthony] Rizzo," Baez said. "I just have to be patient."

At Triple-A Iowa, Baez batted .260 with 34 walks and 130 strikeouts. His .323 on-base percentage and .510 slugging percentage were good for an .833 OPS.